* Soft lockup by using 256K sizes
@ 2009-07-11 0:20 oli1417
2009-07-11 1:11 ` ashford
2009-07-11 1:54 ` Yan Zheng
0 siblings, 2 replies; 4+ messages in thread
From: oli1417 @ 2009-07-11 0:20 UTC (permalink / raw)
To: linux-btrfs
Hello,
I just tried btrfs with a big blocksize (-n,-l,-s) of 256K. Creating the fs worked Ok. I had to put all three -n,-l,-s options to 256K, otherwise mkfs.btrfs complained. But mounting results in a soft lockup (reproducible). It's not the latest btrfs version however. The details are shown below.
Background is the following:
To upgrade the hdd of an old laptop, I used a combination of CompactFlash + CF-to-IDE adapter - a kind of poor-man's SSD solution. With some tuning of /proc/sys/vm/dirty_X settings this is actually really Ok to work with. For erase block aligning I just aligned partitions to 1MiB.
By experimenting with dd I found, that the best write-rates were with 256KiB / 512KiB blocks sizes. This let me to the wild idea to try btrfs with 256K block sizes, so that cow and small file packing would feed the CF with ideal chunks of data.
Well, I don't know really whether this is supposed to work anyhow. I know about the ssd option, but was just curious what it would give for the small file packing. Anyhow ... it soft locked it ;).
Cheers, Oliver
mkfs.btrfs:
---
# mkfs.btrfs -s 256K -n 256K -l 256K /dev/hda3
WARNING! - Btrfs Btrfs v0.18 IS EXPERIMENTAL
WARNING! - see http://btrfs.wiki.kernel.org before using
fs created label (null) on /dev/hda3
nodesize 262144 leafsize 262144 sectorsize 262144 size 4.88GB
Btrfs Btrfs v0.18
#
---
kmsg:
---
[ 447.744830] device fsid 554eb395ef55edc9-b8068222421fcb91 devid 1 transid 9 /dev/hda3
[ 513.252013] BUG: soft lockup - CPU#0 stuck for 61s! [btrfs-endio-met:5137]
[ 513.252013] Modules linked in: btrfs zlib_deflate crc32c libcrc32c sd_mod crc_t10dif usb_storage i915 drm i2c_algo_bit i2c_core binfmt_misc ppdev lp bnep rfcomm l2cap bluetooth michael_mic arc4 ecb lib80211_crypt_tkip acpi_cpufreq cpufreq_powersave cpufreq_userspace cpufreq_stats cpufreq_conservative nfsd exportfs nfs lockd fscache nfs_acl auth_rpcgss sunrpc ext4 jbd2 crc16 fuse dm_crypt dm_snapshot cdc_ether usbnet loop joydev pcmcia ipw2100 libipw snd_intel8x0m lib80211 yenta_socket rsrc_nonstatic pcmcia_core snd_seq_midi snd_rawmidi snd_intel8x0 snd_seq_midi_event snd_ac97_codec ac97_bus snd_seq snd_pcm_oss snd_mixer_oss snd_seq_device snd_pcm psmouse shpchp snd_timer snd soundcore serio_raw snd_page_alloc rng_core dcdbas irda pcspkr pci_hotplug battery button evdev parport_pc parpor
t crc_ccitt ac processor usbhid hid ext3 jbd mbcache ide_cd_mod ide_gd_mod cdrom ata_generic libata uhci_hcd scsi_mod ide_pci_generic ehci_hcd piix intel_agp e100 mii ide_core usbcore video
output agpgart thermal fan thermal_sys dm_mirror dm_region_hash dm_log dm_mod
[ 513.252013]
[ 513.252013] Pid: 5137, comm: btrfs-endio-met Not tainted (2.6.30-1-686 #1) Inspiron 500m
[ 513.252013] EIP: 0060:[<c031df3b>] EFLAGS: 00000246 CPU: 0
[ 513.252013] EIP is at _spin_unlock_irqrestore+0x6/0xb
[ 513.252013] EAX: 00000246 EBX: 00000001 ECX: f65bf5f4 EDX: 00000246
[ 513.252013] ESI: f65bf5e0 EDI: f23c3980 EBP: f23c39a8 ESP: f2103f88
[ 513.252013] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
[ 513.252013] CR0: 8005003b CR2: b7ef56e4 CR3: 3080b000 CR4: 000006d0
[ 513.252013] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
[ 513.252013] DR6: ffff0ff0 DR7: 00000400
[ 513.252013] Call Trace:
[ 513.252013] [<f8839162>] ? btrfs_queue_worker+0x1d4/0x1ea [btrfs]
[ 513.252013] [<f8838ca6>] ? worker_loop+0x73/0x1be [btrfs]
[ 513.252013] [<f8838c33>] ? worker_loop+0x0/0x1be [btrfs]
[ 513.252013] [<c0136740>] ? kthread+0x42/0x67
[ 513.252013] [<c01366fe>] ? kthread+0x0/0x67
[ 513.252013] [<c0103ab7>] ? kernel_thread_helper+0x7/0x10
[ 578.748013] BUG: soft lockup - CPU#0 stuck for 61s! [btrfs-endio-met:5137]
[...]
---
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: Soft lockup by using 256K sizes
2009-07-11 0:20 Soft lockup by using 256K sizes oli1417
@ 2009-07-11 1:11 ` ashford
2009-07-12 9:26 ` Oliver
2009-07-11 1:54 ` Yan Zheng
1 sibling, 1 reply; 4+ messages in thread
From: ashford @ 2009-07-11 1:11 UTC (permalink / raw)
To: oli1417; +Cc: linux-btrfs
Oliver,
> I just tried btrfs with a big blocksize (-n,-l,-s) of 256K. Creating the fs
> worked Ok. I had to put all three -n,-l,-s options to 256K, otherwise
> mkfs.btrfs complained. But mounting results in a soft lockup (reproducible).
> It's not the latest btrfs version however. The details are shown below.
The problem is that the block size is being set to a value that's larger than
the memory page size. This is not supported. I sent in some validation
patches for the MKFS command in January, but they may not have been tested &
integrated yet.
Good luck.
Peter Ashford
Patch #1
# diff -u mkfs.c- mkfs.c
--- mkfs.c- 2009-01-20 11:37:39.000000000 -0800
+++ mkfs.c 2009-01-22 10:13:49.000000000 -0800
@@ -391,14 +391,22 @@
}
}
sectorsize = max(sectorsize, (u32)getpagesize());
+ if ((sectorsize & (sectorsize - 1))) {
+ fprintf(stderr, "Sector size %u must be a power of 2\n",
+ sectorsize);
+ exit(1);
+ }
+
if (leafsize < sectorsize || (leafsize & (sectorsize - 1))) {
fprintf(stderr, "Illegal leafsize %u\n", leafsize);
exit(1);
}
+
if (nodesize < sectorsize || (nodesize & (sectorsize - 1))) {
fprintf(stderr, "Illegal nodesize %u\n", nodesize);
exit(1);
}
+
ac = ac - optind;
if (ac == 0)
print_usage();
#
==========================================================================
Patch #2
It was possible to enter sector sizes larger than a memory page. This would
result in some "unpleasantness", including hangs and crashes. This patch also
adds a minimum sector size of 512 bytes.
# diff -u mkfs.c- mkfs.c
--- mkfs.c- 2009-01-22 13:39:21.000000000 -0800
+++ mkfs.c 2009-01-23 10:01:06.000000000 -0800
@@ -390,8 +390,16 @@
print_usage();
}
}
- sectorsize = max(sectorsize, (u32)getpagesize());
+
+ if (sectorsize < 512) {
+ printf("Sectorsize %u smaller than 512 - corrected\n",
+ sectorsize);
+ sectorsize = 512;
+ } else if (sectorsize > (u32)getpagesize()) {
+ printf("Sectorsize %u larger than pagesize %u - corrected\n",
+ sectorsize, (u32)getpagesize());
+ sectorsize = (u32)getpagesize();
+ }
if ((sectorsize & (sectorsize - 1))) {
fprintf(stderr, "Sector size %u must be a power of 2\n",
sectorsize);
==========================================================================
Patch #3
Yet another patch for mkfs input data verification.
# diff -u mkfs.c- mkfs.c
--- mkfs.c- 2009-01-23 19:26:33.000000000 -0800
+++ mkfs.c 2009-01-23 19:33:07.000000000 -0800
@@ -406,13 +406,23 @@
exit(1);
}
- if (leafsize < sectorsize || (leafsize & (sectorsize - 1))) {
- fprintf(stderr, "Illegal leafsize %u\n", leafsize);
+ if (leafsize < sectorsize) {
+ printf("Leafsize %u smaller than sectorsize %u - corrected\n",
+ leafsize, (u32)getpagesize());
+ leafsize = sectorsize;
+ } else if ((leafsize & (sectorsize - 1))) {
+ fprintf(stderr, "Leafsize %u not a multiple of sectorsize %u\n",
+ leafsize, sectorsize);
exit(1);
}
- if (nodesize < sectorsize || (nodesize & (sectorsize - 1))) {
- fprintf(stderr, "Illegal nodesize %u\n", nodesize);
+ if (nodesize < sectorsize) {
+ printf("Nodesize %u smaller than sectorsize %u - corrected\n",
+ nodesize, (u32)getpagesize());
+ nodesize = sectorsize;
+ } else if ((nodesize & (sectorsize - 1))) {
+ fprintf(stderr, "Nodesize %u not a multiple of sectorsize %u\n",
+ nodesize, sectorsize);
exit(1);
}
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: Soft lockup by using 256K sizes
2009-07-11 0:20 Soft lockup by using 256K sizes oli1417
2009-07-11 1:11 ` ashford
@ 2009-07-11 1:54 ` Yan Zheng
1 sibling, 0 replies; 4+ messages in thread
From: Yan Zheng @ 2009-07-11 1:54 UTC (permalink / raw)
To: oli1417; +Cc: linux-btrfs
2009/7/11 <oli1417@hallo.ms>:
> Hello,
>
> I just tried btrfs with a big blocksize (-n,-l,-s) of 256K. Creating =
the fs worked Ok. I had to put all three -n,-l,-s options to 256K, othe=
rwise mkfs.btrfs complained. But mounting results in a soft lockup (rep=
roducible). It's not the latest btrfs version however. The details are =
shown below.
>
> Background is the following:
>
> To upgrade the hdd of an old laptop, I used a combination of CompactF=
lash + CF-to-IDE adapter - a kind of poor-man's SSD solution. With some=
tuning of /proc/sys/vm/dirty_X settings this is actually really Ok to =
work with. For erase block aligning I just aligned partitions to 1MiB.
>
> By experimenting with dd I found, that the best write-rates were with=
256KiB / 512KiB blocks sizes. This let me to the wild idea to try btrf=
s with 256K block sizes, so that cow and small file packing would feed =
the CF with ideal chunks of data.
>
> Well, I don't know really whether this is supposed to work anyhow. I =
know about the ssd option, but was just curious what it would give for =
the small file packing. Anyhow ... it soft locked it ;).
>
> Cheers, Oliver
>
> mkfs.btrfs:
> ---
> # mkfs.btrfs -s 256K -n 256K -l 256K /dev/hda3
>
> WARNING! - Btrfs Btrfs v0.18 IS EXPERIMENTAL
> WARNING! - see http://btrfs.wiki.kernel.org before using
>
> fs created label (null) on /dev/hda3
> =A0 =A0 =A0 =A0nodesize 262144 leafsize 262144 sectorsize 262144 size=
4.88GB
> Btrfs Btrfs v0.18
>
> #
> ---
>
>
> kmsg:
> ---
> [ =A0447.744830] device fsid 554eb395ef55edc9-b8068222421fcb91 devid =
1 transid 9 /dev/hda3
> [ =A0513.252013] BUG: soft lockup - CPU#0 stuck for 61s! [btrfs-endio=
-met:5137]
> [ =A0513.252013] Modules linked in: btrfs zlib_deflate crc32c libcrc3=
2c sd_mod crc_t10dif usb_storage i915 drm i2c_algo_bit i2c_core binfmt_=
misc ppdev lp bnep rfcomm l2cap bluetooth michael_mic arc4 ecb lib80211=
_crypt_tkip acpi_cpufreq cpufreq_powersave cpufreq_userspace cpufreq_st=
ats cpufreq_conservative nfsd exportfs nfs lockd fscache nfs_acl auth_r=
pcgss sunrpc ext4 jbd2 crc16 fuse dm_crypt dm_snapshot cdc_ether usbnet=
loop joydev pcmcia ipw2100 libipw snd_intel8x0m lib80211 yenta_socket =
rsrc_nonstatic pcmcia_core snd_seq_midi snd_rawmidi snd_intel8x0 snd_se=
q_midi_event snd_ac97_codec ac97_bus snd_seq snd_pcm_oss snd_mixer_oss =
snd_seq_device snd_pcm psmouse shpchp snd_timer snd soundcore serio_raw=
snd_page_alloc rng_core dcdbas irda pcspkr pci_hotplug battery button =
evdev parport_pc parport crc_ccitt ac processor usbhid hid ext3 jbd mbc=
ache ide_cd_mod ide_gd_mod cdrom ata_generic libata uhci_hcd scsi_mod i=
de_pci_generic ehci_hcd piix intel_agp e100 mii ide_core usbcore video
> =A0output agpgart thermal fan thermal_sys dm_mirror dm_region_hash dm=
_log dm_mod
> [ =A0513.252013]
> [ =A0513.252013] Pid: 5137, comm: btrfs-endio-met Not tainted (2.6.30=
-1-686 #1) Inspiron 500m
> [ =A0513.252013] EIP: 0060:[<c031df3b>] EFLAGS: 00000246 CPU: 0
> [ =A0513.252013] EIP is at _spin_unlock_irqrestore+0x6/0xb
> [ =A0513.252013] EAX: 00000246 EBX: 00000001 ECX: f65bf5f4 EDX: 00000=
246
> [ =A0513.252013] ESI: f65bf5e0 EDI: f23c3980 EBP: f23c39a8 ESP: f2103=
f88
> [ =A0513.252013] =A0DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
> [ =A0513.252013] CR0: 8005003b CR2: b7ef56e4 CR3: 3080b000 CR4: 00000=
6d0
> [ =A0513.252013] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000=
000
> [ =A0513.252013] DR6: ffff0ff0 DR7: 00000400
> [ =A0513.252013] Call Trace:
> [ =A0513.252013] =A0[<f8839162>] ? btrfs_queue_worker+0x1d4/0x1ea [bt=
rfs]
> [ =A0513.252013] =A0[<f8838ca6>] ? worker_loop+0x73/0x1be [btrfs]
> [ =A0513.252013] =A0[<f8838c33>] ? worker_loop+0x0/0x1be [btrfs]
> [ =A0513.252013] =A0[<c0136740>] ? kthread+0x42/0x67
> [ =A0513.252013] =A0[<c01366fe>] ? kthread+0x0/0x67
> [ =A0513.252013] =A0[<c0103ab7>] ? kernel_thread_helper+0x7/0x10
> [ =A0578.748013] BUG: soft lockup - CPU#0 stuck for 61s! [btrfs-endio=
-met:5137]
> [...]
> ---
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs=
" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at =A0http://vger.kernel.org/majordomo-info.html
>
current btrfs only supports blocksize =3D=3D PAGE.
(btrfs used to support large block size, but there was race in the
large blocksize code)
Yan
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" =
in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: Soft lockup by using 256K sizes
2009-07-11 1:11 ` ashford
@ 2009-07-12 9:26 ` Oliver
0 siblings, 0 replies; 4+ messages in thread
From: Oliver @ 2009-07-12 9:26 UTC (permalink / raw)
To: linux-btrfs
Hello,
Thanks a lot the explanations. In the v0.18 version used I indeed hit patch #1. The other patches don't seem to (may be in v0.19 ?).
Cheers, Oliver
On Saturday 11 July 2009 03:11:34 ashford@whisperpc.com wrote:
> Oliver,
>
> > I just tried btrfs with a big blocksize (-n,-l,-s) of 256K. Creating the fs
> > worked Ok. I had to put all three -n,-l,-s options to 256K, otherwise
> > mkfs.btrfs complained. But mounting results in a soft lockup (reproducible).
> > It's not the latest btrfs version however. The details are shown below.
>
> The problem is that the block size is being set to a value that's larger than
> the memory page size. This is not supported. I sent in some validation
> patches for the MKFS command in January, but they may not have been tested &
> integrated yet.
>
> Good luck.
>
> Peter Ashford
>
>
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2009-07-12 9:26 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2009-07-11 0:20 Soft lockup by using 256K sizes oli1417
2009-07-11 1:11 ` ashford
2009-07-12 9:26 ` Oliver
2009-07-11 1:54 ` Yan Zheng
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